In a radio communication network using an Internet protocol (IP) suite (hereinafter abbreviated as a “radio IP network” as needed), a so-called mobile IP is provided to improve mobility or a radio communication apparatus (for example, Non-patent Document 1).
The mobile IP uses a care-of IP address (care-of address) which is dynamically assigned according to a position of a radio communication apparatus.
Non-patent Document 1: C. Perkins, “IP Mobility Support (RFC2002)”, [online], October 1996, IETF, [searched on Heisei 18-3-15 (Mar. 15, 2006)], Internet <URL: http://www.ietf.org/rfc/rfc2002.txt>